Derrick Cosby not guilty of voluntary manslaughter in shooting of party guest

Cosby testified in his own defense

Jim Melwert
May 24, 2018 - 1:26 pm
Derrick Cosby

Montgomery County District Attorney's Office


HATFIELD, Pa. (KYW Newsradio) — After two and a half hours of deliberation, a Montgomery County jury has found a Hatfield man not guilty of voluntary manslaughter for shooting a party guest last summer.

Derrick Cosby claimed he shot the man, Jeremy Chasteen, in self-defense.

Cosby testified in his own defense on Thursday. He said he was worried about his daughter, who had recently given birth by cesarean section.

He said Chasteen became enraged that his wife wouldn't get in his car because she thought he was drunk. Cosby said Chasteen stormed into the home, grabbed his wife by the neck, dragging her and swinging at other guests, even knocking down his own mother.

Cosby said other men tried to restrain Chasteen, but "the guy was so big we couldn't stop him." He repeatedly yelled at Chasteen to get out of his house before he pulled a gun and shot Chasteen in the head.

Prosecutors pointed out Cosby didn’t call 911 until after he shot Chasteen, and on redirect Cosby said, "I'll place you in my shoes: This is a guy who has a violent, violent past, who’s known to carry a gun."

Cosby’s attorney Ed Galang said Cosby knew Chasteen served prison time for felony aggravated assault. Cosby said the situation escalated quickly; Chasteen assaulted his wife and his own mother in what seemed like minutes but was only a few seconds.

But prosecutor Richard Bradbury argued the law doesn’t allow you kill because someone is messing up your house or messing up your party.

He says there is no damage to furnishings or other evidence of a prolonged struggle in the room where Chasteen was shot, and no other marks on Chasteen’s body aside from the gun shot wound.

Bradbury told the jury the only question that needs to be answered is did Jeremy Chasteen need to die, and Bradbury argued he did not.